I used to do the same thing! When I started a new job, my puppy was only 6 weeks old (we got him at 4 weeks because he was orphaned) and I was afraid to leave him for 8 hours a day. I would come home at noon for 45 minutes to take him out and play with him. Eventually there was a couple days in which I could not go home, and i got really nervous that he would not be okay by himself. After I realized he was okay and he was getting older, I started gradually decreasing my amount of time going home until I no longer did it. Occasionally I still go home because I work so close to my house, but I never do it on a regular basis anymore.
I think you are just worrying yourself because you see your dog upset. Maybe you should turn the webcam off so you do not have to see. All dogs are upset when they are left alone, but as long as the dog is not exhibiting separation anxiety signs (Digging, chewing, and scratching at doors, howling, barking, and crying for a long period of time, or urination and defecation as a result of distress.), she will be fine.
here's a good website about separation anxiety:
Separation Anxiety | The Humane Society of the United States